They came to protest against Turkish President Tayyip Erdogan, calling him, among other things, a terrorist, for his hardline stance against Turkey's Kurdish community seeking independence.
Erdogan was delivering a speech across the road at the Brookings Institution.
While thousands of miles away, in the Turkish city of Diyarbakir, police were investigating a bomb attack that killed several of their colleagues.
An attack, Erdogan calls outrageous.
(SOUNDBITE) (English) TURKISH PRESIDENT, TAYYIP ERDOGAN, SAYING:
"As we corner the terrorist organizations, the terrorist organization shows its heinous face through such attacks and acts."
Southeastern Turkey has been beset by violence since a ceasefire between the outlawed Kurdistan Workers Party and the government collapsed last July.
Thousands of militants have been killed in the conflict.
Erdogan says his government's fight is a simple matter of Turkish security.
But these protesters says it's time to give the Kurds what they want... and hold Erdogan accountable.

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